Email Send Failure [closed]

Question

If I've list of emailTo address and one of them is invalid.

Does client.Send(email); returns failure/Exception?

Answer 1

Yes and no. For server local addresses (if you send from [e-mail] to [e-mail]) mail server may return error immediately, but generally speaking mail server processes requests asynchronously and does not return any error if recipient address is invalid.

Answer 2

Yes the SMTPClient's Send(MailMessage) method raises a SmtpFailedRecipientsException exception if one or more recipient addresses were incorrect or unreachable.

Answer 3

This is all in the documentation of the SmtpClient class, which you should always read before asking:

When sending e-mail using Send to multiple recipients and the SMTP server accepts some recipients as valid and rejects others, Send sends e-mail to the accepted recipients and then a SmtpFailedRecipientsException is thrown. The exception will contain a listing of the recipients that were rejected.